FPCN39 CWLW 201427
SMOKE CONTROL FORECAST FOR COASTAL BC AND THE INTERIOR INCLUDING THE
NORTHEAST ISSUED BY THE MOUNTAIN WEATHER SERVICE OFFICE OF
ENVIRONMENT CANADA AT 7:00 AM PST SATURDAY 20 FEBRUARY 1999 FOR
TODAY.

VENTILATION INDICES (TEMPERATURE) AND MIXING HEIGHTS.
MIXING HEIGHTS IN METRES ABOVE SEA LEVEL.
AVERAGE WINDS IN KNOTS.

SPOT INDICES ARE DETERMINED BY THE ASPECT AND ELEVATION OF THE SITES.
COMPARE WINDS, TEMPERATURES AND ELEVATION WITH THE SITES HERE
TO DETERMINE THE INDEX IN ANY OTHER AREA.

SOUTHERN INTERIOR

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
FRSR CANYN   KEL      21    2     500   4     39    6     900   4
KAMLOOPS     KEL      16    2     500   4     45    6    1050   5
OKANAGAN     KEL      15    1     500   4     45    6    1050   5
CASTLEGAR    SPOK     19    0     750   4     30    4     900   6
CRANBROOK    SPOK      9   -2     950   8     60    3    1900   7
REVELSTOKE   KEL      12    1     500   4     19    3     700   4

*SUBTRACT 20 FROM THE VENTILATION INDEX IN VALLEYS IF THE MIXING
HEIGHT IS BELOW THE HEIGHT OF THE LOCAL HILLS.

FORECAST UPPER WINDS FOR SATURDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    SE  15   S   35   S   63
CRANBROOK             SE   9   S   24

TODAY'S VENTING: GENERALLY FAIR.


VENTING FOR SUNDAY: FAIR


CENTRAL INTERIOR/NORTHEAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
WILLIAMS L   P.G.     10   -1     950  23     85    2    1500  23
PR. GEORGE   P.G.      9    0     700  24     74    2    1050  15
SMITHERS     P.G.      9   -2     500   6     52    1     900  10
WELLS GRAY   P.G.     10   -2     950  20    100    3    2250  16
FT NLSN      F.N.      9  -11     400   7     19   -6     500   7
FT STJOHN    F.N.      9   -4     700  12      9   -2     700  12

*SUBTRACT 20 FROM THE VENTILATION INDEX IN VALLEYS IF THE MIXING
HEIGHT IS BELOW THE HEIGHT OF THE LOCAL HILLS.

FORECAST UPPER WINDS FOR SATURDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            S   44   S   46
SMITHERS              SE  35   S   46

TODAY'S VENTING: GENERALLY GOOD IN CENTRAL INTERIOR. POOR IN THE
 NORTHEAST.


VENTING FOR SUNDAY: FAIR


COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     27    6     250  11     46    9     400  14
FRASER VLY   QUIL     28    6     250  11     51   10     450  14
SRN VRISL    QUIL     28    7     250   8     42    9     350  11
CNTRL VRISL  QUIL     28    7     300   8     37    8     350  11
NRN VRISL    HRDY     80    6     550  21     94    7     700  23
TERRACE      ANT       9    1     200  13     46    2     600  13
STEWART      ANT       9    1     200  6      28    2     450   4

*SUBTRACT 20 FROM THE VENTILATION INDEX IN VALLEYS IF THE MIXING
HEIGHT IS BELOW THE HEIGHT OF THE LOCAL HILLS.

FORECAST UPPER WINDS FOR SATURDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    SE  50   S   63   S   67
PORT HARDY   SE  59   SE  82   S   98
SANDSPIT     SE  61   SE  57   SE  46

TODAY'S VENTING: GENERALLY FAIR.



VENTING FOR SUNDAY: FAIR.


VENTILATION GUIDELINES:
          0-33.....POOR
          34-54.....FAIR
          55-100.....GOOD.
VENTILATION INDICES NORMALLY DROP TO POOR AFTER SUNSET.


END/GF